ZDZ 60

I have a couple of questions about an older ZDZ 60. I got the engine used, I know! The engine started one time and ran 30 seconds, maybe. Now, I have read alot of threads and tried all the tricks. The engine will ocassionly fire once. It has a Bing carb and a Falkon
ignition. I have taken the plug and checked it for a spark, which it has. I was checking this and answered a call on the cell. After I hung up, (was not turning the prop during call)I noticed it would no longer spark until I turned the ignition off and then back on, is this normal. I know on Evolution gassers this is normal. I read a thread about this engine, where the guy was getting a spark in the cap, and thought the ign was ok until he compared it to another and, as he stated, he got a spark in the cap that was 7-8 mm where with his, the spark was only about 2-3 mm. I know I had a Zenoah 20 that would fire, make a spark and pop but would not run, I had to be convinced the ign was bad , but it was, new one and vvvvrrooom, Comments?? Sorry for the long post.

Next issue: I noticed that when the prop was turnd over a couple of times and then turned backwards it make a poping sound(ign off). A friend said that indicated the rotary valve was to loose and not allowing the carb to work correctly. This seemed to make sense
and being out of ideas I decided to check it. I removed the back plate and inspected the assy. I found that if I moved the plate over th carb opening and blew through the manifold I could move the plate a little and allow a small amount of air through. I figured I had found the problem. I tightened the plate until it sealed better, but still turned freely. Thought I had solved the problem WRONG. Should I undo this adjustment?

Last issue ( I promise) I noticed a lot of guys had replaced the Bing carb with a Walbro 201. Should I do this, if yes will I need a new insulator because of pressure hole location?

All said I think I the main source of my problems is a bad ign module, just wonder if anyone else thought their ign was good but was wrong?